A bit of code cleanup

src/error.rs

@@ -0,0 +1,73 @@
+use std::sync::Arc;
+
+use mlua_sys as lua;
+
+#[derive(Debug, thiserror::Error)]
+pub enum Error {
+    #[error("Syntax error: {0}")]
+    Syntax(String),
+    /// An error returned from lua
+    #[error("Lua runtime error: {0}")]
+    Runtime(String),
+    #[error("Error when running a __gc metamethod")]
+    GcFailure(String),
+    /// Ran into a not enough memory error when trying to grow the lua stack.
+    #[error("Failed to allocate memory")]
+    MemoryAlloc,
+    #[error("Ran into a nill value on the stack")]
+    Nil,
+    #[error("Unexpected type, expected {0} but got {1}")]
+    UnexpectedType(String, String),
+    #[error("bad argument #{arg_index}{} to `{}` ({error})",
+        .arg_name.clone().map(|a| format!(" (name: {})", a)).unwrap_or("".to_string()),
+        .func.clone().unwrap_or("Unknown".to_string())
+    )]
+    BadArgument {
+        func: Option<String>,
+        arg_index: i32,
+        arg_name: Option<String>,
+        /// the error that describes what was wrong for this argument
+        #[source]
+        error: Arc<Error>
+    },
+    #[error("Incorrect number of arguments, expected {arg_expected}, got {arg_count}")]
+    IncorrectArgCount {
+        arg_expected: i32,
+        arg_count: i32,
+    },
+    #[error("There is already a registry entry with the key {0}")]
+    RegistryConflict(String),
+    #[error("Userdata types did not match")]
+    UserdataMismatch,
+    #[error("Missing meta table for userdata")]
+    MissingMetatable,
+    #[error("An error occurred when attempting to convert from a ValueVec at value index {value_idx}, cause: {error}")]
+    ValueVecError {
+        value_idx: i32,
+        #[source]
+        error: Arc<Error>,
+    },
+}
+
+impl Error {
+    pub fn runtime(msg: &str) -> Self {
+        Self::Runtime(msg.to_string())
+    }
+
+    pub fn unexpected_type(expected: &str, got: &str) -> Self {
+        Self::UnexpectedType(expected.to_string(), got.to_string())
+    }
+
+    /// Throw the error in lua.
+    /// 
+    /// This method never returns
+    pub unsafe fn throw_lua(self, lua: *mut lua::lua_State) -> ! {
+        let msg = format!("{}\0", self);
+        let msg_c = msg.as_ptr() as *const i8;
+        lua::luaL_error(lua, msg_c);
+        unreachable!();
+    }
+}
+
+/// A result for use with lua functions
+pub type Result<T> = core::result::Result<T, Error>;

src/main.rs

@@ -26,6 +26,9 @@ use util::*;
 pub mod chunk;
 use chunk::*;
 
+pub mod error;
+use error::*;
+
 fn main() -> Result<()> {
     let lua = State::new();
     lua.expose_libraries(&[StdLibrary::Debug, StdLibrary::Package]);
@@ -198,76 +201,6 @@ impl<'a> PushToLuaStack<'a> for LuaRef<'a> {
     }
 }
 
-#[derive(Debug, thiserror::Error)]
-pub enum Error {
-    #[error("Syntax error: {0}")]
-    Syntax(String),
-    /// An error returned from lua
-    #[error("Lua runtime error: {0}")]
-    Runtime(String),
-    #[error("Error when running a __gc metamethod")]
-    GcFailure(String),
-    /// Ran into a not enough memory error when trying to grow the lua stack.
-    #[error("Failed to allocate memory")]
-    MemoryAlloc,
-    #[error("Ran into a nill value on the stack")]
-    Nil,
-    #[error("Unexpected type, expected {0} but got {1}")]
-    UnexpectedType(String, String),
-    #[error("bad argument #{arg_index}{} to `{}` ({error})",
-        .arg_name.clone().map(|a| format!(" (name: {})", a)).unwrap_or("".to_string()),
-        .func.clone().unwrap_or("Unknown".to_string())
-    )]
-    BadArgument {
-        func: Option<String>,
-        arg_index: i32,
-        arg_name: Option<String>,
-        /// the error that describes what was wrong for this argument
-        #[source]
-        error: Arc<Error>
-    },
-    #[error("Incorrect number of arguments, expected {arg_expected}, got {arg_count}")]
-    IncorrectArgCount {
-        arg_expected: i32,
-        arg_count: i32,
-    },
-    #[error("There is already a registry entry with the key {0}")]
-    RegistryConflict(String),
-    #[error("Userdata types did not match")]
-    UserdataMismatch,
-    #[error("Missing meta table for userdata")]
-    MissingMetatable,
-    #[error("An error occurred when attempting to convert from a ValueVec at value index {value_idx}, cause: {error}")]
-    ValueVecError {
-        value_idx: i32,
-        #[source]
-        error: Arc<Error>,
-    },
-}
-
-impl Error {
-    pub fn runtime(msg: &str) -> Self {
-        Self::Runtime(msg.to_string())
-    }
-
-    pub fn unexpected_type(expected: &str, got: &str) -> Self {
-        Self::UnexpectedType(expected.to_string(), got.to_string())
-    }
-
-    /// Throw the error in lua.
-    /// 
-    /// This method never returns
-    pub unsafe fn throw_lua(self, lua: *mut lua::lua_State) -> ! {
-        let msg = format!("{}\0", self);
-        let msg_c = msg.as_ptr() as *const i8;
-        lua::luaL_error(lua, msg_c);
-        unreachable!();
-    }
-}
-
-/// A result for use with lua functions
-type Result<T> = core::result::Result<T, Error>;
-
 pub trait PushToLuaStack<'a> {
     unsafe fn push_to_lua_stack(&self, state: &'a State) -> Result<()>;
 }

src/userdata.rs

@@ -1,12 +1,9 @@
-use std::{borrow::Borrow, cell::{Ref, RefCell, RefMut}, collections::HashMap, ffi::CStr, marker::PhantomData, ops::{Deref, DerefMut}};
+use std::{cell::{Ref, RefCell, RefMut}, collections::HashMap, ffi::CStr, marker::PhantomData, ops::DerefMut};
 
 use crate::{ensure_type, AsLua, FromLua, FromLuaStack, FromLuaVec, LuaRef, PushToLuaStack, StackGuard, State, Value, ValueVec};
 
 use mlua_sys as lua;
 
-//pub type FieldSetter<T> = fn(lua: &State, this: &T);
-//pub type FieldGetter<T, U> = fn(lua: &State, this: &T, val: &U);
-
 /// An enum representing all Lua MetaMethods
 /// https://gist.github.com/oatmealine/655c9e64599d0f0dd47687c1186de99f
 pub enum MetaMethod {
@@ -92,14 +89,6 @@ impl<'a> PushToLuaStack<'a> for MetaMethod {
     }
 }
 
-pub trait FieldSetter {
-    fn set_field(&self, val: Value);
-}
-
-pub trait FieldGetter {
-    fn get_field(&self) -> Value;
-}
-
 type UserdataFn<'a> = Box<dyn Fn(&'a State, ValueVec<'a>) -> crate::Result<Value<'a>>>;
 
 pub struct UserdataBuilder<'a, T> {